Don't try to do repairs in a dorm or your roommate is going to hate you. Even if you don't have a roommate you will probably make the dorm master unhappy.
Fortunately my roommate is chill, and my DIY stuff doesn't bother him much.
What aspects of electronics interest you? A bunch of microcontroller dev boards, logic analyzers, and breadboard stuff won't do you much good if RF is your interest.
If I built a mobile kit for myself I would be looking at a USB power soldering iron like ts80, USB Oscope/logic analyzer. I decent battery-powered DMM. basic hand tools. Basic consumables like solder, flux, wire, and solvents. But the stuff I picked is because I am into repair. I would not have a set of components I carried around but I would just what I needed as I needed if I didn't have a way storing parts.
I'd like to learn some more on micros but i also like discrete stuff.
I'm not much into RF and i don't think that RF can be breadboarded very easily, manhattan style prototyping would work but that requires soldering.

I want to avoid soldering for now because i don't want to take my soldering station with me. I have a 30W weller but it's one of those dumb soldering irons and takes forever to heat up.
Currently i'm thinking to take all my micros (i don't have that many anyways), my logic analyzer, two DMM's, a pair of breadboards, resistor kit, perhaps my scope.
Maybe a couple LCDs, some encoders, pots. And a bag of gereral purpose MOSFETs, i have some aliexpress fakes that should be fine for breadboard stuff.
Too bad i don't have a capacitor kit to take with me also.
Shouldn't take too much space imo.